Bacterial contamination and infection is a significant problem to public health and in many other areas. Bacterial food borne diseases pose a significant threat to human health, estimated to cause as many as about 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths in the US annually.
For example, in 1996, juice that was contaminated with Escherichia coli was released into the public by a juice maker and resulted in one death and 66 illnesses. The company paid a $1.5 million fine, and the recall alone cost the company $6.5 million. In 2006, an E. coli O157:H7 outbreak from contaminated spinach originating from California resulted in 205 illnesses and 3 deaths. In 2011a listeriosis outbreak from cantaloupes from Colorado in July, August and September resulted in 30 deaths. That is the second deadliest recorded U.S. outbreak in terms of the number of deaths since the Centers for Disease Control and Prevention began tracking outbreaks in the 1970s. Another recall of cantaloupes in 2012 suggests that the food supply is still not safe and highlights the general and pervasive need for additional methods and reagents for testing the food supply to identify contamination.
Another example is bovine mastitis, an infection caused by bacterial cells those results in the inflammation of the bovine breast, reduction in milk yield and a decrease in milk quality. This condition is caused by the bacteria Staphylococcus aureus and Staphylococcus agalactiae. This reduction in milk yields and quality in the western world alone have been suggested to cause annual financial losses of $3.7 billion.
Another example is bovine tuberculosis (Mycobacterium bovis), a bacteria that causes financial loses worldwide. In 2005, for example, 12 of a herd of 55 cattle in a small Michigan farm tested positive for bovine tuberculosis. The farm was forced to destroy the entire herd of cattle, along with an entire herd of hogs. Tuberculosis testing in cattle requires the animal to be held for 2 days, and tests are false positive 5 percent of the time. Often entire herds have to be quarantined or destroyed. The annual worldwide financial losses have been estimated at $3 billion.
Tuberculosis is a leading cause of death worldwide. One third of the world's population is infected with Mycobacterium tuberculosis, the bacterium that causes tuberculosis. Every day 25,000 people are infected and 5,000 people die from the disease. Furthermore, due primarily to poor diagnosis, multidrug resistant strains of M. tuberculosis are emerging and the reemergence of tuberculosis as a worldwide epidemic has become a real threat. The worldwide annual market for tuberculosis diagnostics has been estimated at $1.8 billion.
MRSA is a drug-resistant version of the common Staphylococcus aureus bacteria and is carried by 2.5 million people in the US. A carrier can be a healthy individual, and still be highly contagious, due to the nature of the MRSA bacterium. The bacteria are highly contagious and spread by touch. Approximately 86% of all infections occur within hospitals, and these infections carry a 20% mortality rate. This bacterium costs an average of $21,000 over the standard costs to treat, and kills approximately 19,000 people in the US annually.
Listeria monocytogenes is an intracellular pathogen that can cause invasive disease in humans and animals. Approximately 99% of human listeriosis infections appear to be food borne. While L. monocytogenes has been isolated from a variety of raw and ready-to-eat foods, most human listeriosis infections appear to be caused by consumption of RTE foods that permit postcontamination growth of this pathogen. Listeriosis is estimated to be responsible for about 500 deaths per year in the United States, accounting for 28% of annual deaths attributable to known food-borne pathogens, second only to deaths due to Salmonella infections.
Methods and systems exist for detecting microbial contamination. Such methods and systems suffer from a number of drawbacks, including the need in most cases to remove a potentially contaminated sample from the environment where it is collected and transferring it to a laboratory environment, where the sample is placed in a culture environment for enrichment and growth over a long period of time, ranging from many hours to days. Additionally, because these labs are frequently offsite there is often a delay in the shipping of a sample to a laboratory. Once enriched, samples are typically analyzed using expensive equipment, traditional culturing methods, PCR and other methods. Thus, current processes often comprise a large time lag between sampling and a result, during which time the sampled conditions may have changed and the results of the assay cannot be utilized to diagnose an infection in a patient or to act on contamination in a lot of manufactured food, for example. Accordingly, new composition and methods for detecting microbial contamination are needed. The present invention addresses these needs.